import bcrypt from 'bcryptjs';
import { UsersMongoManager } from "../db/mongo/UsersMongoManager";
import { SecurityManager } from '../managers/SecurityManager';
import { ApiTokenMongoManager } from '../db/mongo/ApiTokenMongoManager';
import { TemporalTokenMongoManager } from '../db/mongo/TemporalTokenMongoManager';
import { BaseController } from './BaseController';
import { NextFunction, Request, Response } from 'express';
import { AuthenticationOption, Token, User } from '../db/interfaces';

export class AuthController extends BaseController {
  security = new SecurityManager();
  usersManager = new UsersMongoManager();
  temporalTokenManager = new TemporalTokenMongoManager();

  async login(req: Request, res: Response): Promise<void> {
    const { log } = req;
    try {
      let token = null
      const { username, password } = req.body;
      this.logger.debug('login', username, password);
      const { valid: isValidPassword, user } = await this._checkPassword(username, password);
      this.logger.debug('isValidPassword', isValidPassword);
      if (!isValidPassword) {
        res.status(401).json({ error: 'Unauthorized' }).end();
        log.error('Unauthorized login attempt for user: ', username);
        return;
      }      
      this._jwtSignUser(user, res)
    } catch (error) {
      this.handleError(res, error);
    }
  }

  _jwtSignUser(user: User | null, res: Response) {
    if (user === null) {
      res.status(401).json({ error: 'Unauthorized' }).end();
      return;
    }
    delete user.hash;
    const token = this.security.signJwt(user);
    if (token === null) {
      res.status(401).json({ error: 'Unauthorized' }).end();
    } else {
      res.status(200).json({ token }).end();
    }
    return;
  }

  async twoFactorCodeAuthentication(req: Request, res: Response) {
    const { code, username } = req.body;
    const { valid: isValid, user } = await this._isValidTemporalCode(username, code);
    if (!isValid) {
      res.status(406).json({ error: 'Unauthorized' }).end();
      return;
    }
    res.status(200).end();
  }

  async _isValidTemporalCode(username: string, code: string) {
    const user = await this.usersManager.getByUsername(username);
    if (user === null || user._id === undefined) {
      return { valid: false, user: null };
    }
    const temporalToken = await this.temporalTokenManager.getByUserAndType(user._id.toString(), TemporalTokenMongoManager.Types.PASSWORD_RECOVERY);
    if (temporalToken === null) {
      return { valid: false, user: null };
    }

    const { token } = temporalToken;
    const valid = bcrypt.compareSync(code, token);
    return { valid, user: valid ? user : null};
  }

  async changePasswordWithCode(req: Request, res: Response) {
    try {
      const { username, newPassword, code } = req.body;
      const { valid: isValid, user } = await this._isValidTemporalCode(username, code);
      if (isValid) {
        await this._setNewPassword(username, newPassword);
        this._jwtSignUser(user, res);
      } else {
        res.status(400).json({ error: 'Code not valid.' }).end();
      }
    } catch (error) {
      this.handleError(res, error);
    }
  }

  async changePassword(req: Request, res: Response) {
    try {
      const { username, oldPassword, newPassword } = req.body;
      const { valid: isValidPassword } = await this._checkPassword(username, oldPassword);
      if (isValidPassword) {
        await this._setNewPassword(username, newPassword);
        res.status(200).end();
      }
      res.status(400).json({ error: 'Password not valid.' }).end();
    } catch (error) {
      this.handleError(res, error);
    }
  }

  async _setNewPassword(username: string, newPassword: string) {  
    const hash = this.security.getHashedPassword(newPassword);
    await this.usersManager.updatePassword(username, hash);
  }

  async _checkPassword(username: string, password: string) {
    let valid = false;
    const user = await this.usersManager.getByUsername(username);
    if (user && user.hash) {
      const { hash } = user;
      valid = bcrypt.compareSync(password, hash);
    }
    return { valid, user };
  }

  static async checkRolesToken(token: Token, rolesToCheck: string[]) {
    if (rolesToCheck.length === 0) {
      return true;
    }

    if (!token._id) {
      return false;
    }

    const tokenFromDb: Token = await new ApiTokenMongoManager().getById(token._id.toString()) as Token;

    if (!tokenFromDb) {
      return false;
    }

    const { roles } = tokenFromDb;
    const validRoles = rolesToCheck.filter((r: string) => roles?.includes(r) || false);
    return validRoles.length === rolesToCheck.length;
  }

  static async checkRoles(user: User, rolesToCheck: string[]) {
    if (rolesToCheck.length === 0) {
      return true;
    }

    if (!user._id) {
      return false;
    }

    const usersManager = new UsersMongoManager();
    const userFromDb = await usersManager.getById(user._id.toString());

    if (!userFromDb) {
      return false;
    }

    const { roles } = userFromDb;
    const validRoles = rolesToCheck.filter((r: string) => roles.includes(r));
    return validRoles.length === rolesToCheck.length;
  }

  static authenticate(options: AuthenticationOption = {}) {
    return async function(req: Request, res: Response, next: NextFunction) {
      const security = new SecurityManager();
      const token = req.headers.authorization;
      const { roles = [] } = options;
      if (!token) {
        return res.status(401).json({ error: 'Unauthorized' });
      }
      try {
        const user: User = await security.verifyJwt(token);
        const validRoles = await AuthController.checkRoles(user, roles);
        if (!validRoles) {
          return res.status(403).json({ error: 'Forbidden' });
        }
        req.user = user;
        next();      
      } catch (error) {
        return res.status(403).json({ error: 'Forbidden' });
      }   
    }
  }

  static tokenAuthenticate(options: AuthenticationOption = {}) {
    return async function(req: Request, res: Response, next: NextFunction) {
      const { log } = req;
      // log.info('tokenAuthenticate')
      try {
        const token: string = req.headers['x-api-key'] as string;
        const dm = new ApiTokenMongoManager();
        const apiToken = await dm.getByToken(token);
        const { roles = [] } = options;
        const valid = !!apiToken && await AuthController.checkRolesToken(apiToken, roles);
        if (!valid) {
          return res.status(401).json({ error: 'Unauthorized' });
        }
        req.token = apiToken;
        next();
      } catch (error) {
        return res.status(403).json({ error: 'Forbidden' });
      }
    }
  }

  static async withUser(req: Request, res: Response, next: NextFunction) {
    try {
      const token = req.token;
      const dm = new UsersMongoManager();
      const user = await dm.getById(token.userId);
      req.user = user;
      next();
    } catch (error) {
      return res.status(403).json({ error: 'Forbidden' });
    }
  }
}